package com.cgx.controller;

import com.cgx.common.R;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;


import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

/**
 * 文件的上传和下载
 */
@RestController
@RequestMapping("/common")
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    /**
     * 文件上传
     *
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file) {
        //上传时的文件名
        String s = file.getOriginalFilename();
        //使用UUID生成一个唯一id，防止文件名重复导致图片被覆盖
        String filename = UUID.randomUUID().toString() + s.substring(s.lastIndexOf("."));
        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在
        if (!dir.exists()) {
            //目录不存在
            dir.mkdirs();
        }
        try {
            file.transferTo(new File(basePath + filename));
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        return R.success(filename);
    }


    /**
     * 文件下载
     *
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void downLoad(String name, HttpServletResponse response) {
        try {
            //输入流读取内容
            FileInputStream inputStream = new FileInputStream(new File(basePath + name));
            //输入流输入到浏览器
            ServletOutputStream outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");  //设置响应回去的是什么类型的文件
            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = inputStream.read(bytes)) != -1) {
                outputStream.write(bytes, 0, len);
                outputStream.flush();
            }
            outputStream.close();
            inputStream.close();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }


    }

}
